Protecting shoes during their manufacture



Feb. 25, 1936. R. SCHNEIDER Er AL PROTECTING SHOES DURING THEIR MANUFACTURE Filed NOV. 27,-1931 Patented Feb. 25, 1936 PATENT OFFICE'.

2,081,674 PROTECTING SHOES DURING THEIR MANUFACTURE Robert Schneider, Paris, and Armand Poelman, Charenton. France, assignors to. Materials Protector Corporation, Newark, N. Y.. a corporation of New Jersey Application November zu, 1931, serial No. 511.668 In 'France December 3, 1930 1o claims.- (ci. 1z-142) Our invention relates to methods for protecting shoes during their manufacture. It has already been proposed to this effect to make use of rubber covers prepared in advance for each shape and each size of shoes. These covers are inconvenient and expensive. Another method consists in forming the protecting coating on the very upper vof the shoe.-

. Our invention concerns a method of the last mentioned kind.

InA this respect, it has already been proposed to utilize matters such as gelatine or nitrocellulose, which are directly applied onto the shoe in the form of solutions and which are subsequently eliminated by-only one possible method, viz. dissolution. In the case of smooth leathers, that process already has a serious disadvantage,

due to the fact that it is impossible to wholly,

to be protected; b is the coating of the coagulat- "remove the coating at the place of the seams. 20 But in the case of shoes made of spongy leathers v and fabric, the process cannot be utilized, because the coating would pass, when dissolved, into the porous support and would deteriorate it completely. 25 Another known method consists in utilizing a A relatively friablecoatin'g, which is subsequently removed by brushing Said coating is liable to crack while in use.' Furthermore, its total elimination is dimcult, so that the pigments entering '30 into the composition of said coating must be of the same colour as the shoe to be protected.-

It has also been proposed to apply onto the shoe a layer of pulverulent matter, on which al film of cellulosic material is produced. 'I'his 35 method then presents vthev same disadvantage as the above mentioned method.

'I'he object of the present invention is to produce on the shoe (made of smooth leather, porous leather or fabric) a protective coating or nlm 40 Iwhich may be removed, when it is no longer necessary, without having to redissolve it or to brush it, but in a simple manner, 'as an onion skin is peeled off.

45 To this effect, in order to form the fllmy coating, we makev use of rubber latex which is applied over a coating of Ia solutionadpted to coagulate the lat'ex, which solution has been previously applied onto the shoe..

' 50 A iilm of gum is formed over the surface of contact between the latex and its coagulant, which film separates the surface of the shoe from the latex which is not yet coagulated. It follows that, when the coagulating solution has naliy permeated the matter to be protected, the

penetration of vthe latex is prevented by the thin film which has begun to form at the beginning of the application of the latex. The latter, by .coagulating completely in the course of time, therefore forms afllm the adhesion of which to 5 the shoe has been reduced to just what is necessary. our invention will be hereinafter described with reference to the accompanying drawing, given merely by way of example vin order to illustrate the method according to our invention and in which: y

Fig. 1 is a diagrammatic sectional view showing a portion of leather at the beginning of the protecting process; t.

. Figs. 2 to 4 are corresponding diagrammatic views illustrating the various stepsy of the process. In these figures, a is the leather, skin. or fabric ing solution; c isthecoating of coagulated latex;

'and d is the layer of latex not yet coagulated.

Fig. 1 shows the leather or fabric coated with the coagulating solution. Fig. 2 shows what takes place immediately followingv the applicationof the latex. The layer of coagulating material bis still present. Between said layer and the latex d, a very thin nlm of coagulated rubber has formed, but the greatest part of the latex still remains liquid. However, when, as shown in Fig. 3, the coagulant has been absorbed or has evaporated, the latex that is still liquid cannot penetrate intothe leather or fabric, from which it is separated by rubber film c, which has been formed from the start and which increases gradualLv. The coagulation of the'latex can there- 35 fore be completed without said latex (Fig. 4) permeating the leather or fabric, which would result in the film of rubberl adhering strongly .to

said leather or fabric. On the contrary, the fllm of rubber which is formed according to our in- 40 vention adheres to .the leather or fabric only to the degree that is just necessary.

We may use for coagulating the rubber latex any of its numerous coagulants, for instance a diluted solution of acetic acid, of iormic acid, `cf citric acid, of hydroiiuoric acid, of boric acid or of phosphoric acid. We may also utilize a solution of a chloride of a bivalent metal, such for instance as calcium chloride, of salts of tribasic acids such persion of .rubber (artificial latex).

lio Care will be taken, when introducing such rials, to add a colloid for avoiding ilocculation.

method according to our invention:

The upper, made of cloth, of a shoe,'which has just been sewn, is placed on a support. We then project thereupon, by means of a sprayer, a very much diluted solution of acetic acid (0.2 N) until the liquid is uniformly spread on the fabric. Im-

mediately after, we project, on the upper, a cer-V taln quantity of latex of a concentration of 40%, vat the rate of from 30 to 40 grammes of latex per minute. 'Ihe latex is al/s/o applied by means of a sprayer, with a pressure of air approximating from 2 to 3 kilogrammes per square centimeter.

From the very beginning of the application 'of the latex, there is formed a very thin film of rubber over which further quantities of latex are ,pplied so as to subsequently obtain a sufficiently` resistant fllmy coating. A quantity of latex ranging between 2 0 and 40 grammes is generally necand, on'the other hand, the concentration of the latex solution, its quantity and the pressure of the air used for atomizing it, we obtain a nlm which maybedetachedmoreorlesseasily. wemaya1so varythepH ofthe latexsoastodiminishits stability and to reduce 'the quantity of coagulant which is necessary to a very low value;

The latex may receive filling materials intendedV to lower its cost price, or to increase itstenacity and to give it an improved resistance to friction.

Hereinafter we give examples of combinations .of the latex solutions' Example 1 Parts in wiht Latex of a concentration-of 60% 100 casein 6 Colloidal clay Instead of using colloidal clay, we may also employ other materials such as, carbonate of magnesia, -zinc oxide, kaolin. lithopone, chalk, carbon black, etc., acting as 'filling materials as above'e'xplained.

In order that .the lm may resist satisfactorily heat and Aultra violet rays. we may use latex which has been previously vulcanized, or introduce, into the' latex, bodies allowing o f subsequent vulcaniaation: v

Parts in weight Latex of a concentration ofv% 4..-- 100 colloidal sulphur 2.5 Zinc oxide v 5 {Vulka P (piperidine piperldyldithlocar bamate) 0. 5

We may also introduce products facilitating lthe ageing (anti-oxygen), such as aldolalphanaphthylamine, phenylbetanaphthylamine.

We may also vulcanize completely a iilm, when it is formed on the shoe, throughclassical means, for instance, by means of sulphur chloride.

Wemayeventuallyvarnishthenlmsoasto ,os'1,e74`. We will hereinafter give,an example of theincrease its resistance to scratching. For this purpose we may use the following varnish:

. Parts in weight The plastic material resulting from polymerization of vinyl' chlor acetate, which itself is obtained through condensationof chlor acetic acid with acetylene 5 I Tpiaonfinn 1 Phenylbetanaphthylamine 5 Benzene s f 'I'he varnish may also be so formed as to stop ultra violet rays, such as, for instance, the following varnish:

Parts in weight Accroid resin 5 Triacetine 1 Alcohol 100 Whilewe have described what we deem to be preferred embodiments .of our invention, it should be well understood that we dp limited thereto as there might be changes made in the composition, concentration and amounts of materials used-,in ourmethod without departing from the principle of our invention as comprehended within the scope ofi the appended What-we claim is:

1. A`method for protecting shoes and similar varticles during their manufacture which com-- vprises spreading a latex coagulant on the surface of said '-shoe and subsequently applying rubber latex on lsaid shoe over said coagulant.

2. A method for protecting shoes and similar articles during their manufacture which comnotwishtobe,

prises spraying 'a latex coagulant on the surface latex on said'shoe over saidl coagulant.

articles during their manufacture which comprises, Aspraying 1a dilutedsolution of acetic acid on said shoe, and subsequently spraying rubber .said aceticacid. 4. A process for protecting shoes and similar articles during -their manufacture which comprises, spreading a latex coagulant on the surface of said shoe and subsequently applying rubber latex mixed with a filling mate'rial for increasing its tenacity on said shoe over said 5. A method for protecting shoes and similar articles during their manufacture, which com- Y prises, spreading a latex coagulant' on the surface of said shoe, subsequently applying rubberlatex on saidshoeover said coagulant, and applying a varnish` over the coag'ulated iilm lof rubber for,

increasing the resistance of said film. 6.`A method off protecting shoes andsimilar I articlesduring their manufacture, which comprises, taking` rubber latex, adding thereto a reagent of an acid character so as to bring it close toits isoelectric point and thus make it capable ofbeingcoagulatedbyasmaliquantityofalatex coagulant, spreading a latex coagulant on the surface of said shoe, and subsequently applying the rubber latex treated as lfirst mentioned on said shoe over said coagulant.

7.Amethod ofprotectingshoesandsimilar l' articles during their manufacture, .which comprises, spreading a latex mulant on the surface of said sh, and subsequently applying an aque.. ous suspension of rubber forming an articial llatex on said shoe over said c'gulant.

3. A method for protecting shoesand similarl of said shoe, and subsequently spraying rubber latex of a concentration of 40% on said shoe over l over said consulent, and subsequently vulcanizing the "thin sheet oiirubber thus obtained.

9. A method of protecting shoes and similar articles during their manufacture-which comshoe over said consulaat,

prises, spreading a latex coagulant over thesurface of said shoe, applying rubber latex on said and 'applylns over the coamxlated iiim of rubber a varnish' adapted to stop ultra. violet rays.

10. .A method articles during their manufacture. which comprises, spreading a latex coagulsnt over the surface of said shoe, and subsequently applying on said shoe over said coagulant a mixture of rubber latex with an anti-oxyge'body for facilitating the ageing. ROBERT SCHNEIDER.

t protectingV shoes and similar 

